Angioplasty is a widely utilized therapeutic treatment in which obstructed intraluminal spaces are reopened or dilated. In a typical procedure, a catheter comprising an inflatable member, such as a balloon, is inserted percutaneously into the patient's luminal passage, such as an arterial passage. Once inserted, the balloon is advanced to the desired treatment site, where the balloon may be inflated to dilate the luminal passage.
Although vascular angioplasty is a widely utilized and largely successful procedure, the procedure can cause collateral trauma to the vessel wall. That is, in order to dilate the area of obstruction, pressure is typically applied, which pressure is realized at the vessel wall. The applied pressure can result in the stretching, or irregular intimal tearing, of layers of the vessel wall, which in turn, can result in restenosis of the treatment site. Any such restenosis that occurs may require further treatment, an outcome that would desirably be avoided.
In order to avoid, or minimize the possibility of such an outcome, devices have been developed that purport to reduce the pressure applied, as well as any potentially resulting collateral damage to the vessel wall. For example, balloons incorporating cutting blades have been provided in conjunction with angioplasty catheters. These cutting balloons, when dilated within a stenosis, provide regular, controlled incisions in the stenosis. It is thought that, unlike irregular intimal tearing, these regular incisions can act to disperse the pressure that otherwise would be realized outwardly at the vessel wall radially about the treatment site, thereby reducing damage to the vessel wall. Although such cutting balloon angioplasty procedures are widely utilized and largely successful procedures, improvements to the same could yet be made.
For example, in some applications, it may be desirable to enhance the precision of the incisions that can be made in a stenosis. Enhanced precision would be advantageous, for example, as it is believed that the sharper and cleaner the cuts provided in a stenosis, the greater the reduction in restenotic response that will be seen. Enhanced precision in the depth of the incision provided would be advantageous as well, inasmuch as such depth precision currently can be difficult to attain, in particular when such cutting elements are provided in conjunction with a compliant balloon.